In figure 6 , the evolution of the lateral displacement D

of the structure has been drawn as a function of the loads that increase factor and this for the three plastic analysis + rigid connections (curve B) plastic analysis + semi-rigid connections (curve of the loading step was limited by the most severe condition, i.e. or A D - that resulted in 48 steps before reaching the collapse and 4 20 seconds of behaviour depending on whether the semi-rigid into account should be noted. instability in the elasto-